Electronic packaging has grown smaller with the advent of integrated circuits that feature a high density, close center line use of input and output interfaces. The trend to smaller devices itself impacts on the design of components that interconnect such devices to the various levels of packaging from chip to chip package, from chip package to daughter board, from daughter board to mother board, and from mother board to the outside world of functioning devices associated with computers, communication circuits, and the like. Center line spacing in these various packages has dropped from 0.250 inches to 0.100 inches over the last decade and now center line spacings of less than 0.050 inches and indeed less than 0.030 inches are being employed. In fact, the inability to design terminals and connectors to interconnect directly on integrated circuit path centers has created a problem expressed in terms of signal distortion, impedance mismatch causing such distortion, and particularly with respect to the manufacture, assembly and use of very small plastic and metal parts needed to define interconnection systems wherein the center lines are appreciably under 0.030 inches.
The foregoing problems manifest themselves with respect to the higher level interconnections in very specific ways. For example, electrical terminals which are typically stamped and formed to be joined to wires as by crimping, I.D.C. (insulation displacement connectors), solder and the like must, in order to be small, require exceedingly small dies operating on very thin metal stock, necessitating special handling in plating, reeling in strip form or special packaging in loose piece form. Moreover, the very small terminals, which are quite delicate and fragile, must be joined to very small wires as by the above-mentioned terminating processes, all necessitating fine precision parts and great skill in handling. The foregoing problem becomes even more difficult in the lower levels of interconnection wherein the center-to-center spacing is even smaller and the interconnection parts are smaller still. This smallness is further complicated when interconnection paths must be utilized in multiple or large line counts where center line distances may need to be on the order of 0.004 to 0.010 inch.
The present invention has as an object the provision of an interconnection system capable of being utilized on fine center distances such as on the order of 0.004 to 0.030 inches for terminals, cable, connectors, and interconnections. The invention has as a further object the provision of a simple and relatively low cost interconnection system that integrates terminal and cable to thus provide an improved electrical characteristic for components and harness units made of such integrated product. The invention has as a still further object the provision of connectors formed on fine centers and of cable formed on fine centers wherein the constituent parts are integral and have characteristics desirable for electrical interconnection.